Table Of ContentMoll. Res. 15: 67-69 (1994).
A new species of Calliostoma from New Zealand
(Mollusca: Gastropoda: Trochoidea)
Bruce A. Marshall
Museum of New Zealand Te Papa Tongewara, P.O. Box 467,
Wellington, New Zealand
Calliostoma (Maurea) simulans n.sp. is described.
Key words: Trochoidea, Calliostoma, new species
Introduction
With the advent of commercial scampi trawling on the Chatham Rise, New Zealand,
during recent years, a number of undescribed invertebrates have been obtained as
bycatch, among them the large calliostomatinae described below. This species
resembles some forms of Calliostoma (Maurea) blacki (Powell, 1950), which has
Overlapping geographic and bathymetric ranges, and with which it is locally sympatric.
It was to have been named in a revision of the New Zealand Calliostomatinae, currently
in progress, but recent requests for identification of scampi bycatch animals have
increased the need for a specific name.
Abbreviations and text conventions
MNZ, Museum of New Zealand, Wellington; NZOI, National Institute of Water and
Atmospheric Research, Wellington; P, primary spiral cord; S, secondary spiral cord.
Spire angle measurements of individual shells were averaged to reduce bias produced
by cyrtoconoid spire outline and increased or decreased expansion rate of the last adult
whorl. Spiral sculptural elements on shells are numbered consecutively adapically to
abapically as defined by Ikebe (1942) and Marshall (1988).
Systematics
Order Vetigastropoda Salvini-Plawen, 1980
Superfamily Trochoidea Rafinesque, 1815
Family Trochidae Rafinesque, 1815
Subfamily Calliostomatinae Thiele, 1924
Genus Calliostoma Swainson, 1840
Calliostoma Swainson, 1840. Type species (by subsequent designation of Herrmannsen,
1846): Trochus conulus Linnaeus, 1758; Recent, north-eastern Atlantic and
Mediterranean.
68 B. A. Marshall
Subgenus Maurea Oliver, 1926
Maurea Oliver, 1926. Type species (by original designation): Trochus tigris Gmelin,
1791; Recent, New Zealand.
Calliostoma (Maurea) simulans n.sp.
Plate 1, figures 1-3
Description: Shell up to 52.5 mm high, most specimens slightly broader than high,
rather thin, anomphalous, glossy, spire 1.0-1.5 x higher than aperture, evenly conical,
mean spire angle 66-81°. Protoconch and first teleoconch whorl white. Subsequent
whorls either white with pale yellowish brown spots between nodules; or spiral
interspaces pale pink through translucent pale buff or almost colourless outer shell
layer, and spiral cords alternately spotted with white and yellowish or reddish brown.
Protoconch 420-430 um wide, sculptured with network of crisp threads that enclose
hexagonal spaces, terminal varix strong. Teleoconch of up to 8.75 strongly and rather
evenly convex whorls, suture well impressed, periphery rounded, base weakly convex.
First 0.2 whorl delineated by a growth scar, with 2 axial costae and fine spiral threads.
Subsequent spire whorls sculptured with spiral cords that multiply by intercalcation
from 4 (P1(cid:8212)P4) to 6 (P1(cid:8212)P4, S1, S2) or, a few specimens 7 by addition of S3; summit
Plate 1. Figures 1-3. Calliostoma (Maurea) simulans n.sp. Figure 1. Holotype, shell height 30.5 mm.
Figure 2. Protoconch of paratype, Pegasus Canyon, 329-183 m, MNZ M.64654. (scale 100
um). Figure 3. Early spire whorls of paratype, Pegasus Canyon 329-183m, MNZ M.64654
(scale Imm).
New Calliostoma
0a
of P4 partly or in a few specimens entirely exposed on spire, nodules rounded; spiral
interspaces considerably wider than each spiral cord, becoming finely spirally lirate.
P1-P4 commencing immediately. P1 at first much weaker than P2 and P3, which are
strong and similar throughout, gradually enlarging to resemble them or remaining
slightly weaker throughout. SI and S2 becoming as large as PI-P4, SI commencing
on late fourth or mid fifth whorl, S2 commencing on mid fourth or early fifth whorl.
Where present, S3 seldom becoming as large as P4. On many specimens P1(cid:8212)P3 nodular
at first; P3 becoming weakly nodular or smooth late on fourth whorl on many
specimens, becoming strongly nodular again after a further 1-3 whorls. SI and S2
rapidly becoming nodular, or S2 becoming nodular 1 or 2 whorls from its inception.
Basal cords similar to those above, numbering 6-9, weaker and more weakly nodular
than those on spire; inner 2 or 3 strongest, nodular; outer spirals more weakly nodular
or smooth, weaker or more or less obsolete; interspaces considerably wider than each
spiral cord, finely spirally lirate. Axial costae strong on first 2 or 3 whorls, obsolete
thereafter. Aperture ovate, inner lip thickened, parietal glaze very thin, outer lip thin
and simple.
Type data: Holotype MNZ M.87450 (height 30.5 mm, width 29.0 mm, 8.3 teleoconch
whorls) and 33 paratypes MNZ: BS 558, 43°30'S, 173°31.3'E, head of Pegasus Canyon,
NE of Banks Peninsula, alive, 27 September 1976, r.v. Acheron. Paratypes (158 MNZ):
BS 786, 43°25'S, 173"26'E, wall of Pegasus Canyon, alive, 329-183 m, 21 February
1979, r.v. Acheron (35); BS 785, 43°25'S, 173°26'E, Pegasus Canyon, alive, 485-
476m, 21 February 1979, r.v. Acheron (59); BS 784, 43°29.5'S, 173°30.5'E, Pegasus
Canyon, alive, 402-338m, 21 February 1979, r.v. Acheron (12); BS 783, 43°31'S,
173°30.5'E, Pegasus Canyon, alive, 256-293m, 21 February 1979, r.v. Acheron (52).
Other material examined: 3 specimens in 3 lots MNZ, and 28 specimens in 13 lots
NZOI.
Distribution: Challenger Plateau, off New Plymouth, off Cape Palliser south to Banks
Peninsula, Chatham Rise, and off Bounty and Campbell Islands, New Zealand, 183(cid:8212)
1006 m, taken alive at 256-410m.
Remarks: Calliostoma (Maurea) simulans most closely resembles C. (M.) blacki
(Powell, 1950), from which it differs in having more strongly convex teleoconch
whorls, and in that spiral cord SI consistently becomes as large as P1 or larger. By
contrast, in C. (M.) blacki S1 seldom becomes as large as P1, and the nodules on P1
are consistently larger than those on S1 before the last adult whorl. The two species
have overlapping geographic and bathymetric ranges, C. blacki occurring on the
Chatham Rise, off the east coast of the South Island from Pegasus Bay southwards, and
off Stewart, Snares, Auckland, Campbell and Bounty Islands (material MNZ and
NZOI). The two species have been obtained living together in dredgings from off
Pegasus Bay, Campbell Island, and the Bounty Islands.
Literature cited
Ikebe, N. 1942. Trochid Mollusca Calliostoma in Japan, fossil and Recent. Japanese Journal of Geology
and Geography 18: 249-282.
Marshall, B.A. 1988. Thysanodontinae: a new subfamily of the Trochidae (Gastropoda). Journal of
Molluscan Studies 54: 215-229.
